Arrangement for starting air cooled internal combustion engines



w. G. MANN MENT F INTERNAL STEGE 2,799,264 0R STARTING AIR COOLED COMBUSTIONENGINES July 16, 1957 ARRANGE 2 Shee ts-Sheet 1 Filed Nov. 25. 1953 I INVENTOR Mlaer S/yenezuv July 16, 1957 w. G. STEGEMANN ARRANGEMENT FOR STARTING AIR COOLED INTERNAL COMBUSTION ENGINES Filed Nov. 25, 1953 2 Sheets-Sheet 2 INVBVIDR Welder 6' Sfgye a ARRANGEMENT FOR STARTING AIR COOLED INTERNAL CGMBUSTION ENGINES Germany, assignor to Werner G. Stegemann, Pinneberg,

Holstein, Germany 9 Claims. (Cl. 123179) The present invention relates to internal combustion engines and, more particularly, to a device for starting air cooled internal combustion engines. In order to start an internal combustion engine, it is necessary either manually or by means of an auxiliary motor to bring the internal combustion engine up to a minimum speed. When starting an internal combustion engine by means of an auxiliary motor, this is usually done by means of a small electric motor receiving its current from an electric battery.

Inasmuch as in particular with larger vehicle engines, the power requirement for the starting of the main motor in cold weather is relatively great, and since furthermore the capacity of an electric battery is rather limited and drops with a drop in temperature, arrangements have been designed according to which the electric starting motor has been replaced by a small internal combustion engine which can be easily started. In order to facilitate the starting of the main motor while preventing damages to the latter, it is additionally advantageous to warm up the main motor prior to the starting of the latter. To this end, it has been suggested to warm up the air stream drawn in by the blower of an auxiliary air cooled motor by causing said air to sweep around the cooling surfaces of said auxiliary motor, and then to convey the thus warmed-up air to the cooling surfaces of the main motor. However, these known arrangements still require considerable time for the starting operation.

It is, therefore, an object of this invention to provide an arrangement for starting a main motor by means of an auxiliary motor, which arrangement will make is possible considerably to reduce the preheating period of the main motor to thereby speed up the starting of said main 7 motor.

It is another object of this invention to provide an arrangement according to the preceding paragraph which will start the main motor only after the latter has been sufficiently warmed up, thereby considerably reducing the wear of said main motor.

it is still another object of this invention to provide an improved starting arrangement including an auxiliary motor for starting a main motor, which arrangement by means of kinetic energy storing means will reduce the starting resistance of the main motor.

Still another object of the present invention consists in the provision of an improved starting arrangement for starting a main motor by means of an auxiliary motor and by preheating said main motor, which will make it possible considerably to speed up the preheating of air for said main motor to thereby materially reduce the starting period for said main motor. 7

These and other objects and advantages of the invention will appear more clearly from the following specification' in connection with the accompanying drawings in which:

Fig. 1 is a side view of an arrangement according to the present invention.

nited States PatentO Fig. 2 is a top view of the arrangement shown in Fig. 1.

Fig. 3 illustrates on a scale somewhat larger than that used in Figs. 1 and 2 a section through a blower for use in connection with the present invention.

Fig. 4 is a side view of the blower shown in Fig. 3.

Fig. 5 is a section through a blower somewhat modified over that of Figs. 3 and 4.

Fig. 6 shows another embodiment of the invention in a partial side view analogous to Fig. 1.

General arrangement The goal of the present invention consists in exploiting the power and the generation of heat of the auxiliary starting motor to a maximum extent for preheating the main motor. This goal has been attained according to the present invention by employing a blower, which is driven by the auxiliary motor for conveying warmed-up air to the cylinders of the main motor, as energy transducer in the manner of an air turbulence brake and to arrange said blower in such a manner that it will transform a maximum portion of the power conveyed thereto into heat which latter will increase the temperature of the air passing through said blower. It will be obvious that such a device will considerably speed up the preheating of the main motor by furnishing in a continuous stream great quantities of heat. If as auxiliary motor a naturally relatively small internal combustion engine is selected, it is possible according to a further development of the invention to employ the entire waste heat of said auxiliary motor for additionally heating the air being conveyed to the main motor. This, it is particularly advantageous to connect the exhaust conduit of the auxiliary motor with the air conduit leading to the main motor and in this way additionally convey the heat of the exhaust gases of the auxiliary motor to said main motor. If desired the heat in the cooling medium of the auxiliary motor may be conveyed to the preheating air for the main motor.

According to a further development of the invention, the heating up of the main speeded up especially in cool weather, by circulating the preheating air stream in a closed circuit in such a manner that the blower draws in the exhaust air of the main motor rather than fresh air.

According to a still further development of the invention, the auxiliary motor in addition to driving the said blower has also connected thereto and drives a mass of fly-wheel, especially a fly-wheel having an energy storing capacity sufiicient to start the main motor. The arrangement is such that after the main motor has been sufficiently preheated, said fiy-wheel is'coupled to said main motor. The stored energy of the correspondingly dimensioned fly-wheel driven at a correspondingly high speed will overcome the starting resistance of the main motor and thus will aid the auxiliary motor in starting the main motor.

Structural arrangement Referring now to the drawing in detail, the arrangement shown in Fig. 1 illustrates a main motor 1 having a plurality of cylinders 2 provided with cooling fins 2a. The said cylinders 2 are surrounded by a hood or cowl 3 through which during the operation of the motor the cooling air taken in by the blower 4 is passed along the cylinders 2. An auxiliary motor 8 is drivingly connected with the crank shaft 5 of the main motor 1 through the intervention of a shiftable clutch 6 and a transmission gear 7. This auxiliary motor 8 is likewise designed as internal combustion engine but is considerably smaller than the main motor. The auxiliary motor 8 drives a blower 9 preferably through the intervention of a shiftable clutch 20. The crank shaft of the auxiliary motor has furthermore connected thereto a fly-wheel 10 of relatively great motor may furthermore be weight. The blower 9 passes the air taken in through its intake connection 11 into a conduit 12 connected to the pressure connection of said blower. The conduit 12 may be passed around the cylinder or cylinders 13 of the auxiliary motor 8 but at any rate leads through the wall of the hood or cowl 3 of the main motor and, preferably at a point near the blower 4. At this portion there is provided a tiltable flap 14 adapted selectively to open or close the mouth of the air conduit 12 or the passage to the connection for the blower 4. At the air exit side of the hood or cowl 3 is likewise provided a tiltable flap 15 by means of which the air discharge or a branch of a conduit.

16 may be opened which returns the air leaving the cowl 3 to the intake connection 11 of the blower 9.

In order to start the main motor 1, the auxiliary motor 8 is started while the clutch 6 is in its ineffective position, and the auxiliary motor then as the fly-wheel 10. The blower 9 passes air through conduit 12 to and by the cooling fins of the cylinder or cylinders 13 of the auxiliary motor which cooling fins convey their heat to the air stream and thus increase its temperature. This stream or flow of heated-up air is pressed into the space between the hood or cowl 3 and the cylinders of the main motor after the flap or throttle 14 has been tilted into its position a in which it closes the connection with the blower 4 which latter is not operated during this operational step. The warmed-up air sweeps over the cylinders 2 of the main motor and the cooling fins 2:: thereof and conveys heat thereto. At the exit end of the hood or cowl 3 there is provided a flap or throttle 15 which at this time occupies its position a so that the exhausted air is through conduit 16 again conveyed to the intake connection 11 of the blower 9. Due to the fact that the revolved quantity of air is repeatedly heated up by the waste heat of the auxiliary motor 8, the said air circulation brings about an ever increasing preheating of the cylinders 2 of the main motor. A similar efiect although at a smaller rate can be brought about without the circulating conduit 16. In this instance, the flap or throttle 15 is moved into the position b which it also occupies during the normal operation of the main motor 1.

dotted lines and designated by the character b.

After the cylinders 2 of the main motor 1 have been into their positions b and b respectively. The preheated main motor 1 is now started by the auxiliary motor 8 so that also the blower 4 is driven and the cooling air stream necessary for the operation of the main motor sweeps over the cylinders 2. The control of the above mentioned shifting movements may uniformly be carried out by a shifting element common to the various parts. In order to overcome the starting resistance offered by the main motor to the starting of the latter, the kinetic energy is made use of which energy has been stored in the correspondingly dimensioned fly-wheel 10. Particularly in view of the great weight of the fly-wheel 10 and also due to the generally relatively high speed of rotation of the auxiliary motor 8, a considerable and at any rate sufiicient quantity of energy can be stored.

The invention also comprises further possibilities to speed up the increase in temperature of the preheating air for the main motor and thus to reduce the entire starting period.

To this end, according to one embodiment of the invention, the exhaust gases of the auxiliary motor 8 may be conveyed to the preheating air by connecting the exhaust conduit 22 of the motor 8 with the conduit 12..

drives the blower 9 as Well.

' 4 ahead of the point where the conduit 12 leads into the cowl 3 see Fig. 6).

According to another modification of the invention, the blower 9 may be so designed that it will take up the complete output of the auxiliary motor 8 at normal operational speed. To this end, the blower may be designed as air turbulence brake as shown for instance in Figs. 3 and 4 by designing the blocks 17 of its runner as plane discs which extend in the axial plane of the runner shaft and move closely along the walls 21 of the blower casing 18 so that a violent turbulence of air and thus an increase in the air temperature is brought about. This effect can tsill be increased further by causing the blades 17a (Fig. 5) to pass by fixed blades 19 of the blower casing 18:: while the space or tolerance between the moving blades and the fixed blades is very small. In this way, practically the entire work of the auxiliary motor 8 is transformed into heat which quickly increases the temperature of the preheating air with the result that the preheating of the main motor and thus the entire starting period is considerably speeded up. Inasmuch as with suchan arrangement the auxiliary motor 8 works at maximum output, also the quantity of heat conveyed by its cylinder or cylinders 13 to the air sweeping around the same and passing through conduit 12 is greatly increased. Since the auxiliary motor 8 has to work only a short time, it is even possible to run the auxiliary motor 8 with an overload without any damage to the motor 8.

It may be added that while it is highly advantageous to place the cylinder or cylinders 13 of the auxiliary motor 8 in the path of the heated air being conveyed to the cylinders of the main internal combustion engine to be started, it should be noted that this is by no means necessary but that the principle of the invention is also applicable if said cylinder or cylinders of the auxiliary motor is or are outside the path of the hot air flowing to the main internal combustion engine.

It is, of course, understood that the present invention is, by no means, limited to the particular construction shown in the drawing but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. In an arrangement comprising an air cooled internal combustion engine and an auxiliary motor operable to start said internal combustion engine, the combination of: clutch means interposed between said internal combustion engine and said auxiliary motor and operable selectively to effect driving connection between said auxiliary motor and said internal combustion engine for starting the latter, blower means arranged for driving connection with said auxiliary motor and including air turbulence producing means frictionally to heat up the air taken in by said blower means to thereby transform into heat a considerable portion of the power conveyed to said blower means by said auxiliary motor, and means conveying the thus warmed-up air from said blower means to said internal combustion engine and around the cylin ders thereof.

2. An arrangement according to claim 1, in which said air turbulence producing means includes plane blades rotatably mounted within said blower means and having at least their side surfaces in close proximity to the adjacent walls of said blower means.

3. An arrangement according to claim 1, in which said air turbulence producing means includes stationary blades connected to the side walls of said blower means and also includes rotatable plane blades having their side surfaces in close proximity to said stationary blades.

4. In an arrangement comprising an air cooled main internal combustion engine and an auxiliary internal combustion engine operable to start said main internal combustion engine, the combination of: clutch means interposed between said main internal combustion engine and said auxiliary internal combustion engine and operable selectively to effect driving connection-betweensaid auxiliary internal combustion engine and said main internal combustion engine for starting the latter, energy transforming means arranged for driving connection with said auxiliary internal combustion engine and operable to draw in air and to convert into heat a considerable portion of the energy imparted upon said energy transforming means by said auxiliary internal combustion engine to thereby heat the air being drawn in by said energy transforming means, means connected to said energy transforming means and leading to said main internal combustion engine for conveying warmed-up air from said energy transforming means to and around the cylinders of said main internal combustion engine, and means arranged to convey waste heat from said auxiliary internal combustion engine to the warmed-up air being conveyed to and around said cylinders.

5. In an arrangement comprising an air cooled main internal combustion engine and an auxiliary internal combustion engine operable to start said main internal combustion engine, the combination of: clutch means interposed between said main internal combustion engine and said auxiliary internal combustion engine and operable selectively to effect driving connection between said auxiliary internal combustion engine and said main internal combustion engine for starting the latter, energy transforming means arranged for driving connection with said auxiliary internal combustion engine and operable to draw in air and to convert into heat a considerable portion of the energy imparted upon said energy transforming means by said auxiliary internal combustion engine to thereby heat the air being drawn in by said energy transforming means, first conducit means conveying the thus heated air to said main internal combustion engine around the cylinders thereof, and additional conduit means connected to the exhaust of said auxiliary internal combustion engine and to said first conduit means.

6. In an arrangement comprising a main air cooled internal combustion engine and an auxiliary internal combustion engine operable to start said main internal combustion engine, the combination of: clutch means interposed between said two internal combustion engines and operable selectively to effect driving connection therebetween to cause said auxiliary internal combustion engine to start said main internal combustion engine, blower means arranged for driving connection with said auxiliary internal combustion engine and including air turbulence produc ing means arranged frictionally to heat the air taken in by said blower means to thereby transform into heat a considerable portion of the power conveyed to said blower means by said auxiliary internal combustion engine, and conduit means surrounding the outer cylinder surface of said auxiliary internal combustion engine and connected to said blower means and leading to said main internal combustion engine to convey warmed-up air from said blower means and heat from said auxiliary internal combustion engine to and around the cylinders of said main internal combustion engine.

7. In an arrangement comprising an air cooled internal combustion engine and an auxiliary motor operable to start said internal combustion engine, the combination of: clutch means interposed between said internal combustion engine and said auxiliary motor and operable selectively to effect driving connection between said auxiliary motor and said internal combustion engine for starting the latter, blower means arranged for driving connection with said auxiliary motor and including air turbulence pro ducing means arranged frictionally to heat the air taken in by said blower means to thereby transform into heat a considerable portion of the power conveyed to said blower means by said auxiliary motor, and closed circuit means extending from the outlet of said blower means to and around the cylinders of said internal combustion engine and from there to the inlet of said blower means.

8. In an arrangement comprising an air cooled internal combustion engine and an auxiliary motor operable to start said internal combustion engine, the combination of: clutch means interposed between said internal cornbustion engine and said auxiliary motor and operable selectively to effect driving connection between said auxiliary motor and said internal combustion engine for starting the latter, blower means arranged for driving connection with said auxiliary motor and including air turbulence producing means arranged frictionally to heat the air taken in by said blower means to thereby transform into heat a considerable portion of the power conveyed to said blower means by said auxiliary motor, closed circuit means extending from the outlet of said blower means to and around the cylinders of said internal combustion engine and from there to the inlet of said blower means, and means arranged within said circuit means and operable selectively to substantially prevent the flow of air from said blower means to said cylinders and from the latter to said blower means.

9. In an arrangement comprising an air cooled internal combustion engine and an auxiliary motor operable to start said internal combustion engine, the combination of: clutch means interposed between said internal combustion engine and said auxiliary motor and operable selectively to efiect driving connection between said auxiliary motor and said internal combustion engine for starting the latter, fiy-wheel means drivingly connected to said auxiliary motor and dimensioned so as to be able to store energy sufiicient to start said internal combustion engine, and blower means arranged for driving connection with said auxiliary motor and including air turbulence producing means operable to convert into heat a considerable portion of energy received from said auxiliary motor to thereby heat up the air taken in by said blower means, and conduit means connected to said blower means and leading to said internal combustion engine for conveying the thus warmed-up air from said blower means to and around the cylinders of said internal combustion engine.

References Cited in the file of this patent UNITED STATES PATENTS 2,155,776 Starr Apr. 25, 1939 

